Colorgrading sky with mask, how to avoid it to overlapping with rest of the frame

[joakim.ox]

hi! i am learning how to change the sky/Color grade it etc, when i do a mask around my sky, and then the camera angle changes, the color grade overlapp with trees etc because the camera is tilting down a bit, is there a solution? 

[Ann Bens]

Animate the mask so it does not cover the trees.

[joakim.ox]

How do i do this? 😃 Thanks